Malicious PDF — malware analysis report

Static analysis result for SHA-256 cdfe094acc1a99e4…

MALICIOUS

PDF

39.5 KB Created: 2020-08-17 00:44:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7)
MD5: 1d12fabf99822b26f2bfdd69fd6f5ce1 SHA-1: 5a20e798eab0a46d2badd6e0fcfc9dc352b212b0 SHA-256: cdfe094acc1a99e4422b654a386a264ea4f22832b292c5d2675f936e937fcc86
152 Risk Score

Malware Insights

MITRE ATT&CK
T1566.002 Spearphishing Attachment T1059.001 PowerShell

The PDF document contains a link that redirects to a known malicious domain, likely as part of a SEO poisoning or phishing campaign. The document body text and embedded URLs suggest a lure related to exam answer keys. The ML classifier strongly indicated maliciousness, and the PDF structure includes a link farm, indicating an attempt to distribute malicious content or traffic.

Machine Learning

  • Nyx PDF Classifier malicious score 1.0000

Heuristics 4

  • PDF links to known malicious redirector infrastructure critical PDF_MALICIOUS_REDIRECTOR_LINK
    PDF contains a clickable URI to redirector infrastructure used by a known malicious PDF SEO/adware delivery campaign. These documents typically rely on user interaction and redirect chains rather than a PDF parser vulnerability.
  • Small PDF contains mass external PDF link farm critical PDF_SEO_LINK_FARM
    Small PDF contains many clickable external PDF links, mostly clustered on one host. This matches generated SEO/link-farm PDF carriers used to route users into malicious or unwanted-software delivery chains, rather than a normal document citation pattern.
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://ttraff.com/pify?keyword=dsssb+je+electrical+answer+key
    • http://jufadiro.southashlandumc.org/uploads/1/3/2/7/132710654/furawekapumob-mamugavekoti-rezojubovig.pdf
    • http://nilopi.thelittlefarmthailand.com/uploads/1/3/0/9/130969341/kitanub.pdf
    • http://nivaki.jamesdicenzo.com/uploads/1/3/1/4/131453574/7916826.pdf
    • https://cdn.shopify.com/s/files/1/0436/2525/0974/files/exam_bubble_sheet.pdf
    • https://cdn.shopify.com/s/files/1/0431/2032/8865/files/dusokajukoxu.pdf
    • https://cdn.shopify.com/s/files/1/0428/9835/8432/files/61086590007.pdf
    • https://cdn.shopify.com/s/files/1/0435/5942/0063/files/types_of_boiler_nptel.pdf
    • https://cdn.shopify.com/s/files/1/0429/9613/8137/files/jifimebefadigal.pdf
    • https://cdn.shopify.com/s/files/1/0431/9726/8128/files/email_contact_form_template.pdf
    • https://cdn.shopify.com/s/files/1/0433/1683/8558/files/jewumixuxodupevagovebud.pdf
    • https://cdn.shopify.com/s/files/1/0427/5834/0774/files/56531580337.pdf
    • https://cdn.shopify.com/s/files/1/0434/0655/7345/files/sokik.pdf
    • https://cdn.shopify.com/s/files/1/0428/3655/7987/files/zukelukov.pdf
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#
    • http://purl.org/dc/elements/1.1/
    • http://ns.adobe.com/pdf/1.3/
    • http://ns.adobe.com/xap/1.0/
    • http://ns.adobe.com/xap/1.0/mm/
    • http://ns.adobe.com/xap/1.0/rights/

Extracted artifacts 2

Files carved from inside the sample during analysis.

FilenameKindSourceSize
font_00_sfnt_off00005cae.bin
1e90394c784175d5c02ecb2548108debdabcb706721c8cd4c794cc536bb2731e
pdf-font-stream PDF embedded font (sfnt) at offset 0x5CAE 5268 bytes
font_01_sfnt_off00006ebd.bin
907d4e7dc8711fa4f2fc293df956b0f1e5527d9febb3dc89399d6e6355be3206
pdf-font-stream PDF embedded font (sfnt) at offset 0x6EBD 10184 bytes